6mm-284 or 6mm-06

Fixing to build one or the other. Anyone have a rifle in either caliber? Hows it shoot? Any load data you would share?

You can buy 6.5-284 brass by Lapua & no necking down from parent brass is required like the 6.5-06. I've heard a Rem. short action is a bit too short for the 6.5-284 using longer heavy 6.5 bullets, so that may be a consideration if you are using a Rem. action.

I use the Lapua 6.5-284 brass in a 25-284 & it lasts a very long time if it's not hotrodded.

Hey sorry I made a typo in the first title. Im gonna build something in the 6mm. Either the 6mm-284 or 6mm-06. Have you had pretty good luck on the 25-284? I should be able to neck down either cartridge pretty easily. I will just use either 6.5-284 brass or 25-06 if I elect to go with the 6mm-06. The action I have is a Remington 700 long action and I have heard the same on building around the 284 case. They swear it will shoot better if built on a long action where you can pull the bullets out further.

I really like the 25-284. It's built on a Winchester length short (Medium?)action (Montana 1999) 3.125 Max OAL. It's throated quite a bit longer than possible with a Rem short action. It pretty much duplicates 25-06 performance. 100 grain at well over 3300 fps & likely more juice in reserve, but the long brass life is nice at sane pressures.

The long Rem action may feed the '06 case better, but for accuracy there just may be something to the shorter, larger diameter case of the -284 based rounds.

Either one necked to 6mm ought to really smoke, though I personally like the 25 or 6.5 bullet choices better for hunting, the 6mm Barnes will surely knock the stuffing out of any critter likely to be encountered & the lighter varmint choices are likely to be pretty spectacular at warp speeds, though probably not too long on barrel life..

If I was able to do it over again, the 6.5-284 would get the nod, just because of no necking down & a few more bullets coming available in the past few years. Just getting old, I guess.

What about 6mm Remington AI? From what I've read 75gr bullet can be pushed pretty easy around 3800fps. I was gonna build one but I am going with something in the 7mm bullet size after talking with my gunsmith.

I really like the 6.5 and .257 too but, I have a 264 Win Mag and a 257 Wby and both shoot really good. The 264 will absolutely melt anything that its pointed at. I have shot many animals with it even at 500+ yards and have yet to have anything take a step. I want something in the 6mm and plan on going with a 12 or 14 twist and shooting the lighter 70-80 grain bullets for varmints but, still being big enough for deer.

There is a poster over on the 24HourCampfire forum named Mark Dobrenski, who goes by the name, "Dober". He lives in Montana and has shot all manner of big game with the 6mm-06. He is an articulate and thoughtful writer with a vast amount of field experience. If I remember correctly, he necks down .25-06 cases to 6mm. In order to avoid confusion with his .25-06 rifles, he uses only nickeled cases to neck down to 6mm.

It would be worth your time to go over to the Campfire and do a search on both your 6mms. You'll turn up lots of info from from some seriously knowledgeable shooters.

I had 6-06 (240 Super Varminter) built on a Ruger 77 action with 26" tube. Made the cases from .270's. Worked fine but didn't do anything for me that a 243 wouldn't have done just as well. I suspect that the differences between individual rifles is almost as great as that between the 6-06 and the 243. Maybe the 6/284 could have been a better mouse trap. But, I'd druther use the 375x45-70 with 283 grains of wheel weights and a compressed charge of slow ball.